1. Field of the Invention
This invention relates to nail construction of the self-clinching type.
2. Prior Art
In many kinds of nailing work, clinching is done, namely that the nail is passed through the wood, after which its tip is bent sidewardly, usually in the direction of the wood grain, and preferably is pressed a little into the wood surface.
In some cases the wood is placed against a suitable support, such as for instance a grooved metal plate, so that the clinching can follow automatically when the nail is driven in from one side of the wood. When the nails are applied by means of so called nail guns or the like, such supports are much affected by the clinching, and the supports become heavily worn, so that they must be repaired or replaced comparatively often.
A proposed remedy to the just mentioned problem a nail whose shank has, at some distance from the point, a weakening so that the nail tip can be bent sidewardly easier, namely by a bending at the place of the weakening. This weakening lies at a distance from the underside of the nail head corresponding to the total wood thickness.
A disadvantage with these known clinchnails is that many different nail dimensions have to be available to fit a variety of different total wood thickness. Another disadvantage is that the clinching may become unsatisfactory as a consequence of rather small variations in the penetration depth of the nails or nail heads. When using the known clinchable nails with a weakening there is a possibility, that the part of the nail shank which is bent sidewardly may loosen due to a rupture at the weakening, whereby the desired effect of the clinching is lost, so that the nail connection is weakened.